/* * Copyright (C) 2023 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package android.graphics.text; /** @hide */ public class GraphemeBreak { private GraphemeBreak() { } /** * Util method that checks if the offsets in given range are grapheme break. * * @param advances the advances of characters in the given text. It contains the font * information used by the algorithm to determine the grapheme break. It's useful * when some character is missing in the font. For example, if the smile emoji * "0xD83D 0xDE0A" is not found in the font and is displayed as 2 characters. * We can't treat it as a single grapheme cluster. * @param text the text to be processed. * @param start the start offset of the queried range, inclusive. * @param end the end offset of the queried range, exclusive. * @param isGraphemeBreak the array to receive the result. The i-th element of the * array will be set to true if the offset (start + i) is a grapheme * break; otherwise, it will be set to false. */ public static void isGraphemeBreak(float[] advances, char[] text, int start, int end, boolean[] isGraphemeBreak) { if (start > end) { throw new IllegalArgumentException("start is greater than end: start = " + start + " end = " + end); } if (advances.length < end) { throw new IllegalArgumentException("the length of advances is less than end" + "advances.length = " + advances.length + " end = " + end); } if (isGraphemeBreak.length < end - start) { throw new IndexOutOfBoundsException("isGraphemeBreak doesn't have enough space to " + "receive the result, isGraphemeBreak.length: " + isGraphemeBreak.length + " needed space: " + (end - start)); } nIsGraphemeBreak(advances, text, start, end, isGraphemeBreak); } private static native void nIsGraphemeBreak(float[] advances, char[] text, int start, int end, boolean[] isGraphemeBreak); }